Modeling by finite elements is nowadays an established technique. Such modeling allows numerically calculating the behavior of objects, which may be very complex. Modeling by finite elements is based on a space division according to a grid made up of finite elements. In addition, during the creation of a finite-element model, a property data set of a modeled entity is generally directly linked with elements of the finite-element model. The property data can define, for example, physical properties of the modeled entity. Such linking of the property data with the finite-element model makes the property data dependant on the granularity on the finite-element model.
In addition, the use of finite-element models is current for the design of complex units, such as aircrafts. Such units require handling complex finite-element models. For example, the finite-element model of an aircraft section, such as the fuselage center section, can comprise more than 33,000 finite elements. Given that a property data set is generally associated with each finite element, it follows that important volumes of property data must be handled for the finite-element model in its entirety.
Traditionally, the design of complex units, such as aircrafts, is made in an iterative way, by successively increasing the granularity of the finite-element model. In other words, the number of finite elements of the finite-element model is modified with each stage of the design. For example, the granularity of the finite-element model is modified as a function of calculations that need to be made, of construction materials and of construction principles used. Consequently, the property data, which are directly dependant on a particular granularity of the finite-element model, must entirely be recreated with each change of the granularity of the finite-element model. A data property set must be created even if the new property data linked to a new finite-element model are identical to the property data linked to a finite-element model on which the new finite-element model is based. This constraint is due to the fact that the property data are linked to the finite-element model by means of a number. This number will be different if the granularity of the model by elements changes, making that there is no possibility of establishing a link between different sets of property data.
Insofar as the property data can be very voluminous, and that, moreover, the creation of the property data requires human intervention at several stages, there will be important constraints, which are reencountered with each iteration of the design, making it impossible to modify the level of granularity of the finite-element model at any time, and accentuating delays in the design process.